Showing papers by "University of Kiel published in 1977"

Nervous outflow from skeletal muscle following chemical noxious stimulation.

Abstract: 1. In order to determine the nervous outflow from skeletal muscle during chemically induced muscle pain, the impulse activity of various types of muscle afferents in response to close intra-arterial injections of pain-producing substances (bradykinin, 5-hydroxytryptamine, histamine and potassium) was studied in anaesthetized cats using a single fibre recording technique. 2. By administration of algesic agents in doses which produce pain in man and pain reactions in animals, about half of the group IV and two thirds of the group III muscle afferents could be activated. In contrast, group II and group I afferent units were usually not excited by chemical noxious stimulation. If effects at all occurred in the thick myelinated afferents, they consisted of a depression of the fibre activity rather than of an activation. 3. The qualitative features of the discharges of group III muscle afferents induced by chemical stimulation resembled those of the group IV units very closely. The group III units differed from the group IV afferents in that their responses to a given dose of bradykinin were of greater magnitude. 4. It is concluded that the chemically induced muscle pain is probably mediated by certain portions of the group IV and group III afferents, whereas the reactions of group II and group I units to algesic agents are such that a contribution to muscular chemo-nociception seems improbable.

Langerhans cells and interdigitating reticulum cells in the thymus-dependent region in human dermatopathic lymphadenitis

Abstract: 14 cases of dermatopathic lymphadenitis were studied by light and electron microscopy. In two instances the ATP-ase reaction was applied to lymphoid tissue. The main morphologic feature of dermatopathic lymphadenitis is an extreme enlargement of the thymus-dependent area which is due to a large number of closely connected, interdigitating reticulum cells (IDC). Enzyme-histochemically IDC are ATPase positive. In all systematically studied cases Langerhans cells are found in the paracortex. They may also be present in the sinuses and the neighbouring lymph node parenchyma. Like IDC, Langerhans cells have an irregularly shaped nucleus, numerous cytoplasmic processes as well as invaginations; in the paracortical area they show intimate connections with each other or with IDC. Frequently they can be differentiated from IDC only by the presence of Langerhans granules. The close topographic apposition to T-lymphocytes typical of IDC is also true of Langerhans cells.

Scanning electron microscopy and epifluorescence investigation of bacterial colonization of marine sand sediments.

Abstract: Scanning electron microscopy (SEM) was employed for the investigation of microorganisms living in marine sand sediments. Epifluorescence, as well as sediment analyses, gave further data on the parameters of the sediment samples. SEM revealed a correlation between the site and density of bacterial colonization and the microtopography of the individual sand grains. Sand grains with a medium roundness showed the greatest density of bacterial colonization. Protected surface sites were favored in the colonization process. The mode of bacterial attachment varied; mostly the barren sand grain surface was colonized. However, bacteria were also observed close to or within detritus or attached to diatoms. Many of the attaching bacteria observed were found to produce polymer strands. In some cases special structures were discovered which could serve bacterial attachment. Entire colonies attached by means of polymer nets, and disc-shaped bacteria were observed.

Organochlorines and heavy metals in the harbour seal Phoca vitulina from the German North Sea Coast

Abstract: Samples of various tissues and organs from healthy, sick and dead harbour seals (Phoca vitulina) from the North German Waddensea collected during the years 1974–1976 were analysed for copper, zinc, total mercury, cadmium lead, and organochlorine pesticide residues (PCB, DDT, Lindane and Dieldrin). The investigations were carried out in order to increase our knowledge about the actual degree of heavy metal and organochlorine pesticide accumulation in these animals. The study was also directed towards a comparison of healthy and sick young seals and those found dead for a possible relation between the condition and concentration of polutants in the organs. There was great variation within all series of compounds investigated, but in general the analytical data obtained indicated that high amounts of heavy metals and organochlorine pesticides can be present even in young seals. An age-specific increase in the mercury and cadmium content in liver samples could be demonstrated. The results are compared with data published by British and Dutch authors for other North Sea regions, and with a few exceptions, no significant differences can be established: cadmium (kidney) and DDT (blubber) contents in areas off the British coast are usually higher than corresponding values for seals from the German coast. There was no clear evidence that the concentrations of any of the compounds investigated had negative effects on the health of the seals. However, possible combined effects cannot be excluded.

Comparison of methods for determining the turnover times of dissolved organic compounds

Abstract: A comparison of two different methods was made using the tracer technique. The first test was performed by adding only one defined amont of a 14C-labelled compound to the sample, the second one by adding different amounts of the same labelled compound, followed by a kinetic approach. In a coastal area of the western Baltic Sea (Kiel Fjord) the turnover times of various compounds (glucose, glucosamine, aspartic acid, leucine, lysine and acetate) were determined. In the open Baltic Sea (especially the Bornholm-Basin) the study was confined to glucose. The variations between the results of the two methods for determining the turnover times are only small for samples from eutrophic or polluted regions. However, larger discrepancies exist with samples from oligotrophic areas. Here, turnover times obtained with the first method were consistently shorter (sometimes only half as long) than, those obtained with the second method. This difference is attributed to the fact that in areas of low bacterial activity e.g. in oligotrophic water bodies, organic-substance uptake by the entire natural population of heterotrophic micro-organisms does not follow exactly the Michaelis-Menten equation. This is likely to be due to a greater population heterogeneity resulting in an increased diversity of uptake characteristics. However, since the calculation of turnover time according to the second method is based on a modification of this equation, errors are introduced.

Four early stages in the development of Li negation

Abstract: No reasonably successful theory of the acquisition of negation seems to have yet been proposed. Most studies describe post hoc what has taken place; but they fail to go on to suggest a theory that will predict what will take place. McNeill seems to be the only one to have explicitly aimed at a theory with at least a certain amount of predictive capacity, but his views leave much to be desired. This paper outlines an alternative proposal to cover four very early stages for the acquisition of negation systems in natural languages. It emphasizes the formal linguistic devices as the major variables that determine the various language-specific developmental sequences.

Extended X-Ray-Absorbtion Fine-Structure Beats: A New Method to Determine Differences in Bond Lengths

Abstract: The superposition of two scattering shells produces beats in the envelope function of the extended x-ray-absorption fine-structure spectrum and a modulation in the scattering phases. From the $k$ values of the extrema in the envelope function and from the inflection points of the phases the separation of these shells can be calculated without knowledge of the scattering phases of the single shells. A resolution in $R$ space up to 0.02 \AA{} can be obtained even in cases where methods used so far are not able to resolve the scattering shells.

Interdependence of ion transport and the action of ouabain in heart muscle

Abstract: 1 The influence of ouabain (0.4 muM) on contractile force and cellular Na and K concentrations was investigated in isolated left atria of the guinea-pig at rest and at different beat frequencies. Simultaneously the binding of ouabain to the tissue was determined.2 Strict dependence of rates of onset of positive iontropic action and of binding of ouabain on beat frequency are limited to conditions where no alterations of cellular Na and K concentrations occur. A correlation was observed between sodium flux per unit time and the development of positive inotropism and binding to the receptors of ouabain.3 Ouabain exerts its positive inotropic effect without affecting the intracellular Na and K concentrations in spite of the fact that under these conditions even the majority of binding sites, i.e. Na-K-adenosine triphosphatases (Na-K-ATPases), are occupied by the drug. The positive inotropic effect may be explained by a ouabain-induced conformational alteration of the Na-K-ATPase which leads to structural alterations of the plasmalemma connected with an increased availability of coupling calcium.4 Increasing the frequency of stimulation over a critical value, which appears to be determined by an overloading of the Na pump, induces a decrease in contractile force, cellular accumulation of Na and loss of K, and eventually contracture.5 The rate of binding of ouabain appears to depend on the actual concentration of particular conformations of the Na-K-ATPase with high affinity for ouabain. These conformations transiently occur during a pumping cycle and their concentration may therefore be dependent on the frequency of cycling which in turn is determined by the frequency of contraction.6 Ouabain can easily be washed out from the tissue irrespective of the condition of the muscle. If, however, the intracellular Na and K homeostasis is impaired, the inhibition of the pump persists even if ouabain is released from the binding sites upon wash-out. It is suggested that the inhibition of the pump is maintained by an increased intracellular Ca ion concentration and a depletion of ATP.7 A kinetic model is proposed for the interaction between cardiac glycosides and the Na-K-ATPase in intact heart muscle cells.

Observations of heterotrophic activity on photoassimilated organic matter

Abstract: The natural heterotrophic utilization of released and particulate photoassimilated compounds by natural phytoplankton populations was followed during the summer of 1975 in the Kiel Bight (Western Baltic Sea). Phytoplankton exudates (2 to 21% of primary production) seem to represent an important substrate for heterotrophic bacteria: uptake rates between 8 and 17,5%/h were observed. Samples incubated with antibiotics indicated that the heterotrophic uptake of phytoplankton exudates during photosynthesis could lead to underestimation of the release rate. Production of 14CO 2was used as an estimate of the mineralization of particulate photoassimilated matter. The mineralization rates measured were in the range of 6 to 20% after 20 h. In order to confirm the quantitative measurements, micro-autoradiographic examinations of the samples were performed.

Growth characteristics of postnatal rat adrenal medulla in culture. A study correlating phase contrast, microcinematographic, histochemical, and electron microscopical observations.

Abstract: Explants and enzyme-dispersed cells of adrenal medulla from 10–12 day old rats were studied in culture for up to 3 weeks. Adrenomedullary chromaffin cells, nerve cells and satellite cells were clearly discernible. The nerve cells were few in number and did not show catecholaminespecific fluorescence. Chromaffin cells stored catecholamines, as judged by the Falck and Hillarp method, in varying amounts decreasing with age of the cultures and the distance from the explants. Exocytosis profiles observed with the electron microscope suggested that cultured chromaffin cells also released catecholamines. Moreover, the cells formed processes and frequently migrated into the outgrowth. After 6 days in culture, the great majority of chromaffin cells stored noradrenaline as revealed by electron microscopy with few adrenaline-storing cells being visible. Granular vesicles (∼ 80–240 nm in diameter) with cores of different electron densities were occasionally present in the same cell suggesting the occurrence of mixtures of primary and secondary amines. Apart from “chromaffin” granules, small clear and densecored vesicles (∼ 40–60 nm) were found both in the somata and cell processes. Chromaffin cells and their processes were often closely apposed and occasionally formed specialized attachment zones. As a whole, chromaffin cells in culture resembled small granule-containing cells in sympathetic ganglia. 0.5 mM dbcAMP prevented dedifferentiation of chromaffin cells as judged by the lack of processes, the size and amount of “chromaffin” granules and the high number of adrenaline-storing cells present after 6 days in culture. NGF caused a striking increase in the number of axons growing out from expiants.

Plasmalemmal calcium in cardiac excitation-contraction coupling.

Abstract: SUMMARY 1. Mammalian heart muscle is extremely sensitive to the external calcium concentration. It reacts to alterations of the external calcium concentration with an immediate adaptation of contractile force. 2. In mammalian heart muscle there is a network of large transverse tubules throughout the cell. These structures are regularly arranged at the level of the sarcomeric Z- and I-lines and increase the cell surface by a factor often. 3. Experimental evidence favours the assumption that the plasmalemma could be the site of a loosely bound superficial Ca fraction which becomes ionized upon depolarization and is again bound upon repolarization of the cardiac cell membrane. 4. A mechanism is discussed which bases the excitation-contraction coupling process on a physicochemical interaction of calcium with membrane phospholipids. The degree of interaction is thought to be governed by the transmembrane electric field, the induced dipole moment of membrane constituents, and proton activity within the membrane.

In-situ investigations on the echinodermAsterias rubens as a predator of soft-bottom communities in the western Baltic Sea

Abstract: In-situ investigations on the life of the common sea star (Asterias rubens L.) were carried out in 1976, employing the Underwater Laboratory “Helgoland“ in Lubeck Bay (Western Baltic Sea). The abundance ofA. rubens amounted to 2–31 m−2 on sediment (fine sand), and to 324–809 m−2 on mobile algal carpets drifting over the bottom. Actual population parameters (abundance, size class distribution) are influenced by both substrate quality and drifting. Stomach investigations revealed prey-size selectivity: Small sea stars feed mainly on the snailHydrobia ulvae when living on the sediment, but on mussel brood(Mytilus edulis) in the phytal. The principal food items of larger sea stars are the sand-dwelling clamMacoma baltica and the phytal-living isopodIdotea baltica respectively.A. rubens is very adaptive to the food available; the diversity of its diet corresponds to the species diversity found in its environment. A change of biotope during active or passive migrations causes switching. The sea star is able to catch motile animals and to dig out infaunal clams. It exhibits a diurnal feeding pattern related to light periodicity; the activity decreases at night. The average frequency of feeding is highly dependent on predator body size; it declines with growth. In-situ experiments indicate an exponential relationship between the feeding duration uponM. baltica and the quotient of clam size to logarithm of sea-star size. An approach is made toward a rough estimate of macrofauna consumption byA. rubens on sediment. The sea star seems to be an important predator and thus a competitor of demersal fishes on soft bottoms of the western Baltic Sea.

"Keratolytic" effect of salicylic acid.

Abstract: The "keratolytic" effect of salicylic acid was examined in guinea-pig skin. Using a fluorescent staining method the str. corneum cells could be seen to rapidly become detached. The cellular walls remained unchanged. This drug therefore appears to primarily reduce the intercellular cohesiveness of the horny cells.

Immunofluorescence-microscopic demonstration of myosin and actin in salivary glands and exocrine pancreas of the rat.

Abstract: Actin and myosin were localized in various salivary glands (parotid, submandibular, sublingual, lingual and Harderian gland) and the exocrine pancreas of rats by indirect immunofluorescence microscopy using specific rabbit antibodies against chicken gizzard myosin and actin. A bright immunofluorescent staining with both antibodies was observed at three main sites: (1) In myoepithelial cells of all salivary glands, (2) in secretory gland cells underneath the cell membrane bordering the acinar lumen (except Harderian and mucous lingual gland), and (3) in epithelial cells of the various secretory ducts (of all glands) in similar distribution as in acinar cells. The present immunohistochemical findings in acinar cells could lend further support to a concept suggesting that myosin and actin are involved in the process of transport and exocytosis of secretory granules.

Treatment of rheumatoid and degenerative diseases with copper complexes: a review with emphasis on copper-salicylate.

Abstract: This review presents a historical account of the treatment of rheumatoid and other degenerative diseases with copper complexes. Clinical data obtained from 1940 to 1971 are provided for about 1500 patients with rheumatoid arthritis (acute or chronic), rheumatic fever, ankylosing spondylitis, staphlococcal spondylitis, gonococcal arthritis, chronic gouty arthritis, polyarticular synovitis, coxitis, disseminated spondylitis, arthritis with psoriasis, Reiter's syndrome, lupus erythematosus, sarcoidosis, arthrosis deformans, erythema nodosum, sciatica (with and without lumbar involvement), cervical spine-shoulder syndrome or lumbar spine syndrome. The drugs used in these studies were Dicuprene, Alcuprin, Cuprimyl, and Permalon, a coppersalicylate preparation. A detailed presentation of toxicities associated with the use of these copper complexes is included.

Effects of systemic hypoxia and hypercapnia on cutaneous and muscle vasoconstrictor neurones to the cat's hindlimb

Abstract: 1. Reactions of cutaneous and muscle vasoconstrictor neurones to the hindlimb on systemic hypoxia and systemic hypercapnia were investigated in chloralose anaesthetized cats. Mainly four types of preparations were used: brain intact and decrebrate (pontomedullary) animals with and without cartotid sinus (CSN) and vagal nerves (VN). 2. In brain intact animals with intact CNS and VN most cutaneous vasoconstrictor neurones were depressed and most muscle vasoconstrictor neurones were excited during systemic hypoxia and hypercapnia. The responses to hypercapnia were smaller than those to hypoxia. 3. In brain intact deafferented animals and in decerebrate animals with and without intact CSN and VN systemic hypoxia and hypercapnia induced excitation in both cutaneous and muscle vasoconstrictor neurones. The responses to hypoxia were significantly smaller in deafferented preparations when compared to those in preparations with intact CSN and VN. Furthermore in muscle vasoconstrictor neurones the size of the responses was not significantly different in decerebrate preparations from that in brain intact preparations. 4. These results indicate a distinct neuronal organization of the chemoreceptor reflexes in the vasoconstrictor systems in the brain stem. Suprapontine brain structures are most important for producing the inhibition of the cutaneous vasoconstrictor neurones during hypoxia and hypercapnia.

Cardiac and respiratory rhythmicities in cutaneous and muscle vasoconstrictor neurones to the cat's hindlimb.

Abstract: Cardiac and respiratory rhythmicities have been investigated quantitatively in postganglionic vasoconstrictor neurones supplying skeletal muscle and skin of the hindlimb in chloralose anaesthetized, immobilized cats. Both rhythmicities are largest in muscle vasoconstrictor neurones, smaller in vasoconstrictor neurones supplying hairy skin, and smallest in vasoconstrictor neurones supplying hairless skin. The magnitude of the cardiac rhythmicity in the vasoconstrictor neurones is positively correlated with the quantitative reaction to systemic hypoxia.

Computerized video-image preprocessing with applications to cardio-angiographic roentgen-image series

Abstract: We report on the enhancement of video-angiocardiographic image-series by digital preprocessing methods including a newly developed technique of interframe subtraction recording as well as computerized image subtraction, integration, and nonlinear representation techniques. Background suppression and noise reduction obtained through these processes applied to roentgen images from animal experiments are demonstrated. Image-series handling and storage are simplified by combining a new method of digitally formatted videotape recording with conventional digital storage of selected image data in the periphery of a minicomputer system.

Simultaneous presence of receptors for complement and sheep red blood cells on human fetal thymocytes.

Abstract: The cells of four thymus glands, two at 12 weeks, one at 16 weeks and one at 22 weeks gestational age, were examined cytochemically for enzymic activity and for surface markers. The reactions for chloroacetate esterase, peroxidase, and alkaline phosphatase were negative and the reaction for nonspecific esterase was only weakly positive in some of the cells. In contrast, nearly all thymocytes at the 12th gestational week showed strong focal acid phosphatase (acP) activity. The number of acP-stainable cells and the staining intensity declined progressively. A high percentage of thymocytes in early fetal life express a complement receptor (CR); the proportion of CR-bearing cells decreased while cells forming rosettes with sheep erythrocytes (possessing erythrocyte receptors: ER) correspondingly increased during fetal life. Using a mixed rosette assay, up to 30% of the thymocytes at 12 weeks gestation were found to bear CR and ER simultaneously. The number of CR- and ER-positive cells also declined progressively with fetal age. These findings show that CR-positive, ER-negative thymus cells mature into CR-negative, ER-positive thymocytes via a CR-positive and ER-positive intermediate cell, indicating that mature ER-positive thymocytes do not originate from another cell line lacking CR. The changes in surface markers during early T cell maturation is relevant to certain lymphomas whose cells also show strong focal acP activity and also express both CR and ER. These lymphoma cells may correspond to fetal thymocytes or T precursor cells present in small numbers after birth.

Functional discrimination of postganglionic neurones to the cat's hindpaw with respect to the skin potentials recorded from the hairless skin

Abstract: 1. Functional characteristics of postganglionic neurones innervating the hairless skin of the cats hindpaw have been analyzed with respect to the skin potentials recorded from the surface of the hair-less skin in chloralose anaesthetized, immobilized, and artificially ventilated animals. 2. Postganglionic neurones of which the activity was closely correlated with the fast transient negative atropine-sensitive skin potentials were called SM (sudomotor) neurones. Other, spontaneously active, postganglionic neurones whose activity was not correlated with these potentials were called VC (vasoconstrictor) neurones. 3. The SM neurones have low resting activity of 0.2±0.1 imp/s (mean±S.D.) or are silent; their axons conduct with 0.77±0.11 m/s. These neurones are activated by vibrational stimuli (tapping on the experimental frame), by noxious cutaneous stimuli, by systemic hypoxia and systemic hypercapnia. Their activity shows respiratory modulation, but no cardiac modulation. 4. The VC neurones have resting activity of 1.1±0.4 imp/s; their axons conduct with 0.52±0.11 m/s. These neurones are inhibited by noxious cutaneous stimuli, by systemic hypoxia and by systemic hypercapnia. Vibrational stimuli inhibit part of these neurones or are without effect. The activity in the VC neurones shows respiratory and cardiac modulations. These functional properties of the VC neurones to the hairless skin are largely identical to those innervating the hairy skin which were investigated recently in our laboratory. 5. The activity of the VC neurones is correlated with slow transient skin potentials which are atropine resistant. Decrease of the activity in these neurones is accompanied by slow transient skin potentials with positive polarity.

Biosynthesis of N‐Glycolylneuraminic Acid in Porcine Submandibular Glands

Abstract: 1. The morphology of porcine submandibular gland tissue is demonstrated by light and electron microscopy. 2. Subcellular particles from porcine submandibular glands were prepared by a procedure adapted to the presence of viscous mucus, and were fractionated on continuous and discontinuous sucrose gradients. 3. Six particulate fractions were obtained by discontinuous gradient centrifugation. These were identified by electron microscopy, marker enzymes and nucleic acid content and were designated as follows: (1) plasma membranes, (2) smooth membranes and light Golgi membranes, (3) heavy Golgi membranes, (4) membrane mixture and mitochondria, (5) mitochondria and (6) membrane mixture and mucin residues. The bulk of rough membranes and cell nuclei was found in the 3000 ×g sediment before fractionation. 4. Sialyltransferase and N-acetylneuraminate monooxygenase showed highest activities in the Golgi membrane fractions representing 45% and 36%, respectively, of total tissue activity. The specific activities of these membrane-bound enzymes were respectively 13 and 10 times higher when compared with the homogenate. 5. The acylneuraminic acid/protein ratio was lowest in the Golgi membranes when compared with the other particulate fractions and the cytosol glycoprotein. The molar N-acetylneuraminic acid/N-glycolylneuraminic acid ratio was highest in the two Golgi membrane fractions (average 45:55) and in the pool of free acylneuraminic acids (41:59), and lowest in the cytosol glycoprotein (10:90). 6. Approximately 2.6% of the total acylneuraminic acids occurring in porcine submandibular glands are freely diffusible, 80% of them representing free N-acetylneuraminic acid and N-glycolyl-neuraminic acid in a molar ratio of about 4:6 and 20% representing cytidylyl-glycosides of N-acetylneuraminic acid and N-glycolylneuraminic acid in a ratio of 6:4. 7. In radioactive labelling experiments with surviving slices of porcine submandibular glands the highest specific radioactivities were found in the pool of free acylneuraminic acids, followed by N-acetylneuraminic acid and N-glycolylneuraminic acid bound to the Golgi membranes. N-Acetylneuraminic acid and N-glycolylneuraminic acid of the cytosol glycoproteins have lowest turnover rates. 8. Based on these experiments a model is presented describing two pathways of N-acetylneuraminic acid modification in the course of glycoprotein biosynthesis. At least 40% of N-acetylneuraminic acid is hydroxylated before its transfer onto Golgi membranes and linkage to growing glycoprotein molecules and about 50% thereafter. This results in a molar N-acetylneuraminic acid/N-glycolyl-neuraminic acid relationship of 1:9 in the secreted glycoprotein. It is assumed that free N-acetylneuraminic acid is modified by the soluble cytosol monooxygenase whereas the glycoprotein-bound N-acetylneuraminic acid is hydroxylated by the corresponding membrane-bound enzyme.

A Natural Clay Organic Complex from Andalusian Black Earth

Abstract: Protein complexes of smectites in soils are difficult to detect if the usual smectite tests show no peculiarities. Andalusian black earths are typical examples. Investigation of the alkylam- monium derivatives, however, allows detection of adhered macromolecules which might be protein-like although this cannot be proved cxactly. Investigation of artificial clay-protein complexes reveals different types of clay protein interactions. Calcium smectites adsorb proteins mainly on the external surfaces, the macromolecules being anchored in the interlayer spaces. Sodium smectites give partial crystalline products in which the silicate layers are distributed in the protein matrix. Exchange of alkylammonium ions can be used as a tool for detection of the protein. If this is adsorbed on external surfaces (calcium smectites) the increased layer separation during the cation exchange enables the macromolecules to slip between the layers and the basal spacing of the alkylam- monium derivatives are changed in characteristic ways. The partial crystalline sodium clay-protein complexes are reorganized by alkylammonium ions to regular structures. The proteins are not displaced completely from the silicate surfaces so that the basal spacing of the alkylammonium derivatives are enhanced in comparison with pure montmorillonite.

Trennung stereoisomerer gemischter Hexahalogenokomplexe von Osmium (IV) durch Ionenaustauschchromatographie

Abstract: Die gemischten Hexahalogenokomplexe [OsClnX6–n]2−, X = Br, J; n = 1–5 einschlieslich der fur n = 2, 3, 4 existierenden Stereoisomerenpaare werden durch Ionenaustauschchromatographie an Diathylaminoathylcellulose (DEAE) mit verdunnten Mineralsauren getrennt. Die spektrophotometrische Untersuchung ergibt, das die fruher durch stereospezifischen Ligandenaustausch mit anschliesender ionophoretischer Isolierung erhaltenen cis- bzw. trans-Komplexe nicht vollig rein sind. Separation of Isomeric Mixed Hexahalo Complexes of Osmium(IV) by Ion Exchange Chromatography The mixed hexahalo complexes [OsClnX6–n]2−, X = Br, I; n = 1–5 including the pairs of stereoisomers for n = 2, 3, 4 are separated by ion exchange chromatography on diethylaminoethylcellulose (DEAE) with diluted mineral acids. The spectrophotometric investigation shows, that the cis- resp. trans-complexes formerly prepared by stereospecific ligand exchange and ionophoretic isolation are not really pure.

Vereinfachte Schädelidentifizierung nach dem Superprojektionsverfahren mit Hilfe einer Video-Anlage

Abstract: Die fotografische Schadelidentifizierung durch das bekannte Superprojektionsverfahren konnte durch Verwendung einer Video-Anlage modifiziert und entscheidend verbessert werden. Das auf elektronischer Bildmischung beruhende Identifizierungsverfahren ist methodisch einfach zu handhaben und bietet dem Untersucher die Moglichkeit, in wesentlich groserem Umfang die Beziehungen zwischen Knochen- und Weichteil-proportionen und den Strukturen der Knochenoberflache und den Einzelheiten der Weichteilform als konkret fasbare Identitatsmerkmale zu erkennen. Die grose Anzahl an kontrollierbaren Merkmalen gestattet es, bei dem hohen Mas an Individualitat, das der Kopf bietet, nicht nur entweder „ein gutes Hineinpassen“ oder „ Nichthineinpassen“ eines Schadels in eine Fotografie, sondern einen Identitats-beweis oder-ausschlus zu erreichen.

Photoabsorption of alkali and alkaline earth elements calculated by the Scaled Thomas Fermi method

Abstract: Photoionization cross sections have been calculated by means of the Scaled-Thomas-Fermi method for the alkali metals and the alkaline earths. Using these results the absorption coefficients for bound-free transitions have been obtained for thermal plasmas of 6000 to 20,000 K and wavelengths from 500 to 10,000 A. In addition the oscillator strengths are given for the principal series of the alkali metals.